AveXis gains after revealing SMA study details

Gene therapy company AveXis Inc. (NASDAQ:AVXS) added $10.65 (22%) to $58.66 after it announced the design of a planned pivotal study of AVXS-101 to treat spinal muscular atrophy (SMA) type 1. The 20-patient, single-arm trial is to use historical, natural history data as a comparator. AveXis plans to begin the trial in 1H17.

In a September meeting and subsequent communications, AveXis said FDA acknowledged its rationale for the single-arm design. AveXis plans to evaluate developmental improvement, defined as the ability to sit; and efficacy as measured by "event-free" survival, defined as survival without requiring at least 16 hours of ventilation support per day for more than two weeks in the absence of an acute reversible illness. FDA recommended that the company evaluate both developmental improvement and efficacy as co-primary endpoints...